Investigation of biogenic amines in sufu (furu): A Chinese traditional fermented soybean food product

This study was carried out to investigate the biogenic amine content and chemical properties of sufu (furu, in Chinese mandarin), a traditional cheese-like fermented soybean food product produced in China. Thirty-eight samples of sufu collected from the retail market and factories, which had been manufactured in various regions in China, were divided into white, red and grey sufu according to the dressing mixtures used for maturing the product. The biogenic amines and chemical properties exhibited large variations among samples of the same type and brand. Moreover, no consistent significant correlation between the biogenic amines and the chemical properties among the three types of sufu was observed. At least five of the ten biogenic amines studied were found in each type of sufu. In the three types of sufu, putrescine and cadaverine were the most commonly found biogenic amines, and putrescine and tyramine were those in the largest proportions. Serotonin and agmatine were not detected in any sample. The mean total biogenic amine content in grey sufu (570.5 +/- 386.4 mg/kg, wet weight basis) was higher than that in white sufu (153.6 +/- 160.2 mg/kg) and red sufu (10.9 +/- 11.6 mg/kg). Five out of 28 white sufu samples posed histamine intoxication risk (over 50 mg/kg). Therefore, avoidance of excessive consumption of sufu on a regular basis is recommended. The findings suggest sufu should be manufactured under strict hygienic conditions to minimize the biogenic amine content of sufu and its associated risks to health. (c) 2012 Elsevier Ltd. All rights reserved.